Racer Session #064 | Brandon Lucia | April 17, 2011
Experimentation is a big part of what goes on at Racer. Players frequently aim at making new sounds with their instruments, or forging new interactions between players, in written compositions as well as during improvisations. Experimental performances are often self-evident characterizations of interesting, and in some cases novel musical ideas.
In improvisation, players often push their instruments, and explore the boundaries of what is possible using conventional instruments. In many cases, these experiments involve non-standard techniques for playing: for example, playing the body of a cello by rubbing a slightly sweaty hand over it. In other cases, these experiments entail novel combinations of constraints on players – at racer, we’ve seen performances using the spatial layout of the players to dictate what and when to play and using rules distilled from the rules to playground games to dictate how players interact.
Compositions presented by prior curators also exhibit elements of experimentation. Aaron Otheim’s composition for detuned piano was interesting in that it relaxed the constraint dictating that the instrument being played was sound. Steve Tressler’s session discussed the weird physical phenomena that dictate how we hear music, and illustrated the concepts of alternate harmonic frameworks, like just intonation. The list could go on, but I want to discuss this week’s session.
For this week, I have written a piece of software that I will be playing in lieu of a conventional instrument. I like to give projects that I work on stupid names, so I have decided to call the software that I will be playing the Chango. Chango is, amongst other things, a Romanian ethnic minority, the Yoruba god of thunder, a Korean percussion instrument, and a latin ska band; This software is not named after any of those things.
The operation of the Chango is structured around a set of “emitters”. The emitters are arranged in two-dimensional space in a regular grid (although hypothetically, they could be arranged in any geometric form). Each emitter has an assigned frequency (e.g., A4) and produces a sine wave at that frequency. The amplitude of each emitter’s wave is determined by an “intensity map” that overlays the space in which the emitters are arranged. The intensity map is a two dimensional grid of values between 0% and 100%, that computes an amplitude for each emitter.
One way to visualize this arrangement is to consider that the emitters rest on a plane in a three-dimensional space, and the intensity map is a curvy surface sitting over the top of the plane. The height of each point in the curvy surface at a given point is the amplitude of the emitter beneath that point in the plane. The curvy surface is not fixed. Instead, the position of the mouse cursor dictates the peak of the surface, and from that peak, a mathematical function determines the rate at which the amplitude decreases with distance. All emitters are always producing sound. The amplitude falloff function is arranged so an emitter’s amplitude is very rarely zero (meaning most of the time an emitter’s sound is audible).
There is one trigger per emitter. The trigger raises the pitch of the emitter by one half step. So by repositioning the cursor, a player can continuously vary the harmony being produced, and by using the triggers, a player can cause discrete variations in frequencies that make up the current harmony. These two mechanisms factor into the question asked in the experiment: can these two simple primitive operations be used to create music? Furthermore, what are the challenges – harmonically, rhythmically, and notationally – to writing music for the Chango?
The name of the piece I am presenting is “No Air”. It is called No Air for several reasons. First, all emitters are continuously producing sound, so there is “no air” between the notes being played. Second, the composition is for solo Chango; No Air is a reference to the fact that human action is no pre-requisite for producing music. Chango would go on playing if I left the stage. No Air is unfortunately unfinished. I will be performing the first two movements. There is a third movement planned that I have not had time to write, because it requires additions to the Chango software.
I have developed a notation for scoring Chango music that I found convenient. I will bring a printed score for anyone interested, and briefly discuss my notation before performing. I have also released the Chango, and will release the score to No Air on the internet at https://github.com/blucia0a/Chango.